The goal of this project is to perfect pars plana vitreous surgery by: l) Improving surgical instrumentation; 2) Improving photographic documentation of intraocular findings and manipulations; 3) Studying the potential prognostic value of preoperative rubeosis; 4) Studying potential damage to the retina from light sources used during vitreous surgery; 5) Finding methods to help prevent the devastating effects of intraocular cellular proliferations as they are found in retinal detachments and after perforating injuries, resulting in massive folding of the retina; 6) Learning to understand disease processes of the vitreous by means of histologic and electromicroscopic investigation of vitreous biopsy specimens.